SSL_want(3) OpenSSL SSL_want(3)NAME
SSL_want, SSL_want_nothing, SSL_want_read, SSL_want_write,
SSL_want_x509_lookup - obtain state information TLS/SSL
I/O operation
SYNOPSIS
#include <openssl/ssl.h>
int SSL_want(SSL *ssl);
int SSL_want_nothing(SSL *ssl);
int SSL_want_read(SSL *ssl);
int SSL_want_write(SSL *ssl);
int SSL_want_x509_lookup(SSL *ssl);
DESCRIPTIONSSL_want() returns state information for the SSL object
ssl.
The other SSL_want_*() calls are shortcuts for the
possible states returned by SSL_want().
NOTESSSL_want() examines the internal state information of the
SSL object. Its return values are similar to that of
SSL_get_error(3). Unlike SSL_get_error(3), which also
evaluates the error queue, the results are obtained by
examining an internal state flag only. The information
must therefore only be used for normal operation under
non-blocking I/O. Error conditions are not handled and
must be treated using SSL_get_error(3).
The result returned by SSL_want() should always be
consistent with the result of SSL_get_error(3).
RETURN VALUES
The following return values can currently occur for
SSL_want():
SSL_NOTHING
There is no data to be written or to be read.
SSL_WRITING
There are data in the SSL buffer that must be written
to the underlying BIO layer in order to complete the
actual SSL_*() operation. A call to SSL_get_error(3)
should return SSL_ERROR_WANT_WRITE.
SSL_READING
More data must be read from the underlying BIO layer
in order to complete the actual SSL_*() operation. A
call to SSL_get_error(3) should return
SSL_ERROR_WANT_READ.
SSL_X509_LOOKUP
The operation did not complete because an application
callback set by SSL_CTX_set_client_cert_cb() has asked
to be called again. A call to SSL_get_error(3) should
return SSL_ERROR_WANT_X509_LOOKUP.
SSL_want_nothing(), SSL_want_read(), SSL_want_write(),
SSL_want_x509_lookup() return 1, when the corresponding
condition is true or 0 otherwise.
SEE ALSOssl(3), err(3), SSL_get_error(3)17/Aug/2001 0.9.6j SSL_want(3)
